Polymers of carbon monoxide and olefins, generally referred to as polyketones, are well known in the art. The polyketone polymers of the subject invention are of a specific linear alternating type. Such polymers have utility as premium thermoplastics in the manufacture of a wide variety of shaped articles.
The addition to a polymer of a nucleating agent, to promote crystallization of the polymer from the melt, is also well known in the art. Nucleating agents allow faster processing of a polymer, and provide a more uniform microstructure because smaller spherulites form upon melt crystallization. Products molded from polymers containing a nucleating agent generally exhibit improved physical and mechanical properties.
The use of foreign materials as nucleating agents is highly selective, and there is no universally strong nucleating agent for all polymers. A nucleating agent effective for one polymer may be ineffective for even a closely related polymer. Similarly, a compound closely related to an effective nucleating agent for a given polymer, may be ineffective in that same polymer.
In general, the efficacy of a nucleating agent is indicated by an increase in the crystallization temperature for a polymer, preferably when the nucleating agent is present at a low level of addition. Higher crystallization temperatures are generally indicative of faster crystallization rates. For the production of molded articles, faster crystallization rates allow higher production rates.
It is an object of this invention to provide an effective nucleating agent for a polyketone polymer. In particular, it is an object of this invention to provide polyketone polymer compositions containing an effective amount of a graphitic nucleating agent.